Squidward

Squidward is an iOS framework that reduces the plumbing required for creating constraints in code using auto layout. The api is to match the current anchor system as much as possible so the learning curve is small and the magic is minimal. Here are the main use cases to help you get started.

How to install via Cocoapods

pod 'Squidward', :git => 'https://github.com/QuarkWorks/Squidward.git', :tag => '{{version}}'

Edge Anchors

// From
NSLayoutConstraint.activate([
    view.topAnchor.constraint(equalTo: superView.topAnchor, constant: 10),
    view.leftAnchor.constraint(equalTo: superView.leftAnchor, constant: 20),
    view.bottomAnchor.constraint(equalTo: superView.bottomAnchor, constant: -30),
    view.rightAnchor.constraint(equalTo: superView.rightAnchor, constant: -40)
])

// To
NSLayoutConstraint.activate([
    view.edgeAnchors.constraint(equalTo: superView.edgeAnchors,
        constant: UIEdgeInsets(top: 10, left: 20, bottom: 30, right: 40))
])

Center and Size Anchors

// From
NSLayoutConstraint.activate([
    view.centerXAnchor.constraint(equalTo: superView.centerXAnchor, constant: 10),
    view.centerYAnchor.constraint(equalTo: superView.centerYAnchor, constant: 20),

    view.widthAnchor.constraint(equalTo: superView.widthAnchor, constant: 30),
    view.heightAnchor.constraint(equalTo: superView.heightAnchor, constant: 30),
])

// To
NSLayoutConstraint.activate([
    view.centerAnchors.constraint(eqaulTo: superView.centerAnchors, constant: UIOffset(horizontal: 10, vertical: 20)),
    view.sizeAnchors.constraint(equalTo: superView.sizeAnchors, constant: UIOffset(horizontal: 20, vertical: 30))
])

Assignment and Priority within an Activate Statement

// From
var leftConstraint: NSLayoutConstraint! = view.leftAnchor.constraint(equalTo: superView.leftAnchor)
leftConstraint.priority = UILayoutPriorityDefaultLow

NSLayoutConstraint.activate([
    leftConstraint,
])

// To 
NSLayoutConstraint.activate([
    view.leftAnchor.constraint(equalTo: superView.leftAnchor)
        .prioritize(at: .defaultLow).assign(to: &leftConstraint),
])

Specific Corner Anchors

// From
NSLayoutConstraint.activate([
        view.leftAnchor.constraint(equalTo: superView.rightAnchor),
        view.topAnchor.constraint(equalTo: superView.bottomAnchor)
])

// To
NSLayoutConstraint.activate([
    view.cornerAnchors(for: .topLeft).constraint(eqaulTo: superView.cornerAnchors(for: .bottomRight))
])

Specific Edge Anchors

// From
NSLayoutConstraint.activate([
    view.leftAnchor.constraint(equalTo: superView.leftAnchor),
    view.topAnchor.constraint(equalTo: superView.topAnchor),
    view.bottomAnchor.constraint(equalTo: superView.bottomAnchor),
])

// To
NSLayoutConstraint.activate([
    view.edgeAnchors.constraint(edges: [.left, .top, .bottom], equalTo: superView.edgeAnchors)
])

Directional Edge Anchors

// From
NSLayoutConstraint.activate([
    view.topAnchor.constraint(equalTo: superView.topAnchor, constant: 10),
    view.leadingAnchor.constraint(equalTo: superView.leftAnchor, constant: 20),
    view.bottomAnchor.constraint(equalTo: superView.bottomAnchor, constant: -30),
    view.trailingAnchor.constraint(equalTo: superView.rightAnchor, constant: -40)
])

// To
NSLayoutConstraint.activate([
    view.directionalEdgeAnchors.constraint(equalTo: superView.edgeAnchors,
        constant: DirectionalEdgeInsets(top: 10, leading: 20, bottom: 30, trailing: 40))
])